/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */


bool isSameTree(struct TreeNode* p, struct TreeNode* q)
{
     if(p==NULL&&q==NULL)
     return true;

     if(p!=NULL&&q==NULL||p==NULL&&q!=NULL)
     return false;

     if(p->val!=q->val)
     return false;
    
      return isSameTree(p->left,q->left)&&isSameTree(p->right,q->right);
}